Regardless of Saturday's result in the decider, the world No.15 will arrive in Melbourne with the weight of the nation on her shoulders - and that won't bother her in the slightest, Dellacqua says.

"She genuinely wouldn't be fussed, she couldn't care less about expectation, for her it's about the performance she puts in and what she gets out of it," Dellacqua said.

"It's a really tough place being a tennis player, and it's a lonely, brutal sport.

"Just having a friend, it helped me having Ash at the end of my career, and I've probably helped her starting her career. It's one of those stories where two worlds collide and we've had each other."

Barty started playing doubles with Dellacqua when she was just 15, and the pair were runners up at the Australian, Wimbledon and US Opens in 2013, and runners-up at the French Open in 2017.

Barty had quit tennis in 2014, and played cricket for the Brisbane Heat's WBBL team in 2015/16, before returning to the court in 2016, sparking a dramatic rise through the rankings over the past 18 months.

Barty rekindled her love of sport while playing cricket with the Brisbane Heat in the WBBL. Picture: Colleen Petch.

Barty cites her settled personal life, including her relationship with golfer Garry Kissick, as the key to her on-court success.

"I'm in a very happy place on and off the court, my private life is my private life, I'm certainly having a good time with my friends and loved ones, but I'm in a nice place and it's definitely coincided with why I'm playing such good tennis,' she said.